Embracing the irregular: a patient-specific image processing strategy for visual prostheses

Abstract

We propose a stimulation strategy for retinal prostheses that makes use of irregular shapes of elicited phosphenes. It is patient specific and thus relies on prior psychophysical measurements. Visual perceptions are stored in a phosphene map that relates stimulation parameters to the visual stimulus elicited. Based on this map, stimulation parameters are chosen in such a way that the edges of the target image are optimally represented through the shape of the phosphene. In a psychophysical pilot study, we compare this approach to one in which we choose phosphenes to match the brightness of the target image. We find that participants perform similarly well with both strategies overall. Howeve..